Spectrally Resolved Approach for Modeling Short Pulse Amplification in Er$^{3+}$-Doped Fibers

Abstract

Abstract-We study pulse propagation in Er 3+ -doped fiber amplifiers (EDFA) within the framework of a spectrally resolved pulse rate-propagation equations model. Our model accounts for the effects of gain dispersion, gain saturation, waveguide and chromatic dispersion, and amplified spontaneous emission. This model allows us to approximate the effects of nonlinear resonant dispersion on short pulse amplification in doped fibers, without reverting to the generalized nonlinear Schroedinger equation. Numerical results of the time-dependent power spectrum of the amplified pulse demonstrate subpicosecond pulse propagation in EDFAs.Index Terms-Erbium (Er), optical fiber amplifiers, optical fiber dispersion, optical pulse amplifiers.

Ultrashort-Pulse High-Power ${\hbox {Yb}}^{3+}$-Doped Fiber Amplifiers

“…We also demonstrated that by tuning the pump power, the amount of spectral compression of a negative-chirp incident pulse can be controlled. Our results provide additional support to experimental measurements of broad-bandwidth amplified pulses, which extends the standard NLSE formalism and can, in principle, be compared directly with the pulse spectrogram [10]. Furthermore, the model allows the inclusion of a realistic gain spectrum for the Stark-splitted doped ions transitions using measured cross sections, therefore alleviating some of the restrictions imposed by analytical gain approximations [7].…”

“…In the spectral range relevant to optical amplification, i.e., at nm (see inset), the dispersion is normal, and it monotonically increases from to ps km nm . Thus, gain-induced dispersion fluctuations are expected to have only small effect on an amplified pulse, in contrast to Er -doped fibers [10]. In what follows, we demonstrate the effects of various physical parameters on the spectral and temporal characteristics of a short amplified pulse.…”

“…Thus, spectral broadening is most significant for a pulse incident near the gain peak wavelength, e.g., at nm. It is worth to mention, however, that the amplified spectrum of a weak pulse is predominantly affected by gain narrowing [10]. We note that the pulse gain is relatively small in the short tail of the gain spectrum, e.g., for nm, and hence spectral broadening is also small.…”

“…Digital Object Identifier 10.1109/JQE.2007.902390 pulses in single-clad doped fibers, taking into account spatially and spectrally resolved gain and dispersion contributions, fiber nonlinearity, and amplified spontaneous emission (ASE) noise [10], [11]. Second, we extend previous works on pulsed YDFAs and describe numerical calculations using parameters that were not considered in detail before, such as the pulse wavelength, pulse peak power, Yb concentration, pump filling factor, fiber length, pumping configuration and pump power.…”

Neodymium, erbium, and ytterbium co-doped fiber amplifier

“…[24][25][26][27][28] The rate equations describe the relations among the excited states of all the ions. The equations in this model include the pumping power absorption by Er, Yb, and Nd ions, forward and backward energy transfers, ASE, and scattering losses.…”